In a known bar sensor as a measuring instrument, the electric coil is wound on a coil form in which a flow conductor piece with a permanent magnet has been inserted (DE-PS No. 24 10 630). At the forward face of the bar sensor is a pole shoe which interacts with a revolving sprocket ring on a wheel, to measure the driving speed of a motor vehicle. The electrical connection of the coil is made via two conductor rails at whose one end there is contact with a coil connection, and at whose other end there is contact with a conductor strand of a connector cable. The connecting end of the cable and of the other bar sensor components is spray-coated with plastic. The disadvantage of such solutions is that all functionally important tests of the measuring device, such as measuring the signal voltage, the coil resistance, the insulation test, and the dimensions of the sensor, can only be made when the connecting cable is already connected with the conductor rails. Because of this, the sensor is very difficult to handle in the course of manufacturing as well as in testing. Thus all the testing and manufacturing processes cannot be fully automated.
The present solution is an attempt to perform all manufacturing stages and all functionally important tests of the measuring device as automatically as possible, without being obstructed by the connecting cable.